Wärtsilä 20

The Wärtsilä 20 has proven its robustness and reliability with over 6000 engines delivered since its introduction to the market in the early 1990s. The engine can switch from MDO to HFO and vice versa without power interruption at any engine operation load.

The Wärtsilä 20 engine is fully compliant with the IMO Tier II exhaust emissions regulations set out in Annex VI of the MARPOL 73/78 convention.


    Exellent fuel flexibility allowing operation on HFO, LBF, MDO and ultra low sulphur fuel. Low fuel oil consumption over a wide load range.

    Utmost power-to-weight and power-to-space rations in combination with a great flexibility in engine support arrangements allows optimised rigid or flexible installation for a wide range of vessel applications.

    High reliability and proven in service makes the Wärtsilä 20 an excellent choice for any application.

    Technical data
    Wärtsilä 20 IMO Tier II or III
    Cylinder bore 200 mm Fuel specification: Fuel oil
    Piston stroke 280 mm 700 cSt/50°C
    Cylinder output 200 kW/cyl 7200 sR1/100°C
    Speed 1000rpm ISO 8217, category ISO-F-RMK 700
    Mean effective pressure 27.3 bar SFOC 185 g/kWh at ISO cond.
    Piston speed 9.3m/s
    Option: Common rail fuel injection.
    Dimensions (mm) and weights (tonnes)
    Engine type A* A B* B C* C D F Weight
    4L20    - 2510    - 1348    - 1483 1800 725   7.2
    6L20 3254 3108 1528 1348 1580 1579 1800 624   9.3
    8L20 3973 3783 1614 1465 1756 1713 1800 624 11.0
    9L20 4261 4076 1614 1449 1756 1713 1800 624 11.6

    Wärtsilä 20

    Rated power
    Engine type kW
    4L20    800
    6L20 1 200
    8L20 1 600
    9L20 1 800

    The Wärtsilä 20 can be installed as prime mover for smaller applications like small cargo vessels, small tankers, ferries, Fishing vessels, tug boats and Offshore supply vessels and as Auxiliary engine in vast range of applications.

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